It is known to attach one material to another with a fastener such that the head of the fastener lies just below the upper surface of the one material. For example, it is known to countersink the head of a screw fastener below the surface of a sheet of material being secured to another. It is also known to fill the space between the countersunk screw head and the surface of the material with a dowel having an upper surface flush with the upper surface of the material.
It is also known to provide a drill bit capable of drilling both a hole for a screw and a countersink hole for recessing the head of the screw. United States Patent Application Publication 2008/0307627 (Gertner) describes a system utilizing such a drill and also using plugs for filling the countersink holes. The plug is typically of the same material as the material being secured and is preferably secured in the countersink hole by an adhesive.
To make a suitable bond between the plug and the hole, typically, the plug is rolled over a puddle of the glue or otherwise coated until the cylindrical surface is fully coated. Then, the plug is inserted into the hole and driven flush or near flush with a hammer. The types of glue used vary, but typically PVA glue, epoxy, urethanes and other types of “carpenter's glue” are used in this application. The most suitable glue for the application may be determined by repetitive testing involving ASTM as well as other customized methods including environmental exposure conditions.
In using the known methods, there is a considerable collection of extra glue as the glue-coated plug is driven into the hole, which can make a mess on the face of the hammer as well as stain the wood in the vicinity of the glue joint unnecessarily. Each joint on the surface of the wood needs to be cleaned thoroughly and, of course, the hammer cleaned as well. The process is inherently time consuming and cumbersome.